In a case of photographing a living body, such as a vein, which is positioned under a skin, there is a method in which light is radiated from a palm side of a hand or a pad side of a finger and transmitted light that is transmitted to a backside of the hand or a backside of the finger is used. For example, PTL 1 discloses a method of obtaining a vein pattern of a finger by, in a state where a grip such as a doorknob is grasped, radiating light from a pad side of the finger and detecting transmitted light, which is transmitted through the finger, by an image capture unit arranged on a backside of the finger.